I'm trying to replace the oil seal front pinion bearing on my 85 k5 blazer. Do I have to take the whole differential apart or can I remove the yoke and pull the bearing? Thanks in advance for any advice.

 

If you are replacing the outer pinion bearing due to failure, then the race likely needs to be replaced as well. Typically the race is driven out from inside the diff which would require the pinion to be removed. I guess it might be possible to use a slide hammer with a low profile hook to pull the race out. Then you could carefully drive in the new race and put it all back together. Proper preload on the bearings might be tricky though with mixed new/used bearings and no real way to set rotational torque as is commonly used when setting up pinion bearing preload.

If just replacing a leaking pinion seal, it is as simple as marking the pinion yoke & nut for proper alignment to the shaft & counting the number of exposed threads outside of the nut, then remove the nut & flange to get at the seal. Reinstall lining up your marks with the proper number of threads exposed and it should be good to go. If the nut gets put back on to the same location, preload should be maintained.

 

I may do the smart thing and allow someone with experience to do the job then. Maybe they can let me shadow. I appreciate your fast response. I came about this issue while driving I heard a sound that reminded me of a lose fly wheel. When I parked and inspected the fly wheel was find but I had a lot of slack in my drive shaft and yoke and it was leaking from the differential. I've removed the drive shaft and have a replacement. I'm glad I didn't yank the yoke off now. What a disaster that would have been....